This invention relates to security mailboxes and, in particular, to single door, rural mailboxes.
It is well known that mailboxes are susceptible to pilfering. The problem is particularly acute in rural areas where a mailbox may be located at some distance from a residence. Furthermore, a rural mailbox may be left isolated and unobserved for extended periods of time.
The typical rural mailbox has a single door which is held closed by a simple door pull which engages a catch on the mailbox in a spring-like fashion. While such mechanisms are simple and durable, and are easily accessible by a postal carrier, they provide no means for locking the mailbox and thus are equally accessible to a passing thief.
It is therefore desirable to have a rural mailbox which resists destruction or violent entry and which may be locked after mail is placed in the mailbox so as to prevent unauthorized access. Locks may be easily provided for a mailbox, but the mailbox must remain accessible to the postal carrier both to retrieve outgoing mail and to deposit incoming mail. It is desirable, therefore, that a security rural mailbox may be opened once by a postal carrier and thereafter locked so as to prevent access by anyone other than the postal patron. Various solutions have been proposed for this problem. One common solution is to employ a double door on the mailbox. U.S. Pat. No. 4,382,540 issued to Kelly, et al. on May 10, 1983 for "Double Door Security Rural Mailbox" discloses a mailbox of this type having a locking mechanism such that a front door may be opened and closed once by the mail carrier before being secured in a locked position. Thereafter, the front door may only be unlocked by unlocking and opening the rear door.
A variation on this concept is disclosed in U.S. Pat. No. 5,400,960 issued to Jeffs on Mar. 28, 1995 for "Letter Locker Mailbox Assembly." Jeffs discloses a mailbox having an upper mail receiving compartment communicating by a mail chute to a lower outgoing mail tray. The door to the upper mail receiving compartment is held closed by a magnetic strip. The upper door is sized so that a would-be thief is unable to reach in to the mail stored in the outgoing mail tray. The mail receiving compartment is secured by a locked door.
Another solution to this problem is disclosed in U.S. Pat. No. 4,726,512 issued to White on Feb. 23, 1988 for "Self Locking Means." White discloses a locking mechanism whereby an inner lock box is formed within a standard rural mailbox. The mailbox may be opened one time after which the inner lock box is placed in a closed and locked position such that a key is required to reopen the inner lock box.
A further solution to this problem is disclosed in U.S. Pat. No. 5,407,126 issued to Coultas, et al. on Apr. 18, 1995 for "Single Door Security Mailbox." Coultas, et al. disclose a locking mechanism for a single door rural mailbox. The lock is provided with a set position allowing the mail carrier to open the closure once after which the closure is closed with sufficient force so that the locking mechanism passes the set position and engages in a locked position. Thereafter, the closure may only be unlocked by the owner with a key.